<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta http-equiv="X-UA-Compatible" content="IE=edge">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
    <style>
        b{
            background-color: red;

            /* 设置无效 */
            width: 500px;
        }

        address{
            width: 150px;
            background-color: #000;
            color: white;
        }
    </style>
</head>
<body>
    <b>行内元素</b> <b>行内元素</b>
    <address>江苏省</address>
</body>
</html>